A task force (TF) is a unit or formation established to work on a single defined task or activity. Originally introduced by the United States Navy, the term has now caught on for general usage and is a standard part of NATO terminology. Many non-military organizations now create "task forces" or task groups for temporary activities that might have once been performed by ad hoccommittees.

The concept of a naval task force is as old as navies, but the term came into extensive use originally by the United States Navy around the beginning of 1941, as a way to increase operational flexibility. Prior to that time the assembly of ships for naval operations was referred to as fleets, divisions, or on the smaller scale, squadrons, and flotillas.

Before World War II ships were collected into divisions derived from the Royal Navy's "division" of the line of battle in which one squadron usually remained under the direct command of the Admiral of the Fleet, one squadron was commanded by a Vice Admiral, and one by a Rear Admiral, each of the three squadrons flying different coloured flags, hence the terms flagship and flag officer. The flag of the Fleet Admiral's squadron was red, the Vice Admiral's was white and the Rear Admiral's blue. (The names "Vice" (possibly from advanced) and "Rear" might have derived from sailing positions within the line at the moment of engagement.) In the late 19th century ships were collected in numbered squadrons, which were assigned to named (such as the Asiatic Fleet) and later numbered fleets.

A task force can be assembled using ships from different divisions and squadrons, without requiring a formal and permanent fleet reorganization, and can be easily dissolved following completion of the operational task. The task force concept worked very well, and by the end of World War II about 100 task forces had been created in the U.S. Navy alone.

These are temporary organisations composed of particular ships, aircraft, submarines, military land forces, or shore service units, assigned to fulfill certain missions. The emphasis is placed on the individual commander of the unit, and references to “CTF” are common. CTF is an abbreviation for “Commander, Task Force”.

In the U.S. Navy, task forces as part of numbered fleets have been assigned a two-digit number. "In March of 1943, Cominch [Commander-in-Chief, United States Fleet, Admiral Ernest J. King] instituted the system of numbering all fleets, assigning the even numbers to the Atlantic and the odd to the Pacific. This resulted in adding fleet designations to the titles of the various forces in the theater: Naval Forces, Europe, became the Twelfth Fleet; South Atlantic Force the Fourth Fleet; and Naval Forces, Northwest African Waters, the Eight Fleet. The Atlantic Fleet, itself, was designated the Second Fleet. The standardization of fleet designation led to a definite system in task force designation.[1] A force was numbered with two digits - the first being that of the fleet from which the force was taken and the second indicating the sequence in that fleet. Task group within a force were numbered by an additional digit separated from the TF number by a decimal point. To indicate a task unit within a group, another decimal point and digit were added. Thus, the third task unit of the fifth task group of the second task force of the Sixth Fleet would be numbered 62.5.3."

This arrangement was typically abbreviated, so references like TF 11 are commonly seen. Likewise the force is broken down as following: task force, task group, task unit, and task element. In addition, a task force could be broken into several task groups,[2] identified by decimal points, as in TG 11.2, and finally task units, as in TU 11.2.1. Individual ships are task elements, for example TE 11.2.1.2 would be the second ship in TU 11.2.1.

Note that there is no requirement for uniqueness over time. The United States Seventh Fleet used TF 76 in World War II, and off Vietnam, and continued to use TF70-79 numberings throughout the rest of the twentieth century, and up to 2012.

In government or business a task force is a temporary organization created to solve a particular problem. It is considered to be a more formal ad hoc committee.

A taskforce, or more-commonly task force, is a special committee, usually of experts, formed expressly for the purpose of studying a particular problem. The task force usually performs some sort of an audit to assess the current situation, then draws up a list of all the current problems present and evaluates which ones merit fixing and which ones are actually fixable. The task force would then formulate a set of solutions to the problems and pick the "best" solution to each problem, as determined by some set of standards. For example, a task force set up to eliminate excessive government spending might consider a "best" solution to be one that saves the most money. Normally, the task force then presents its findings and proposed solutions to the institution that called for its formation; it is then up to the institution itself to actually act upon the task force's recommendations.